Final answer:
The number of red fish at the pet shop is 45, calculated by using the ratio of blue to red fish (2:3) and knowing that there are 30 blue fish.
Step-by-step explanation:
The student asked: The ratio of the number of blue fish to the number of red fish at a pet shop is 2 to 3. There are 30 blue fish at the pet shop. How many red fish are at the pet shop?
To solve this, we can set up a proportion based on the given ratio. If the ratio of blue fish to red fish is 2:3, then for every 2 blue fish, there are 3 red fish. Given there are 30 blue fish, which is 2 times 15, we can multiply the other half of the ratio (3) by 15 as well to find the number of red fish.
Step-by-step calculation:
Identify the ratio of blue to red fish, which is 2:3.
Since there are 30 blue fish, divide 30 by the blue ratio number (2) to find how many times the ratio has been multiplied, which is 15 times.
Multiply the red ratio number (3) by 15 to find the number of red fish: 3 * 15 = 45 red fish.
Therefore, there are 45 red fish at the pet shop.